Location
Senegal / Africa
Project record
Dakar Mamelles desalination intake and brine discharge
Dakar's first large seawater desalination plant is in its commissioning year after Eiffage recorded a 340 m seawater-intake microtunnel milestone in July 2025. The 50,000 m3/day plant was still under construction during a supervision visit in February 2026. The older JICA design basis also carried a separate 500 m brine-discharge line; current public updates leave its final geometry, installation and marine acceptance unconfirmed.
Segment
Marine utilities
Status
Plant remained under construction in February 2026; commissioning was expected later in 2026, while final marine handover evidence remains unpublished / Confirmed
Last checked
19 July 2026
Coverage
Related sectors
Marine utilities is the primary work classification. Related sectors connect this record to adjacent marine delivery and market coverage.
Subject index
Related subjects
These subject pages bring together related projects, technical articles, reports, and evidence methods.
Project anatomy
Contract scope and delivery roles
- Client / authority
- Société Nationale des Eaux du Sénégal (SONES)
- Delivery parties
- Toyota Tsusho-led consortium with Eiffage Génie Civil and VA Tech Wabag, TPF consultancy and supervision
- Contract route
- JICA ODA loan SE-P3; international competitive CP-1 design-build and operating package awarded to the Toyota Tsusho-led consortium, with two years of operation and maintenance after construction
- Execution window
- Toyota Tsusho's 2022 order carried a 2025 planned completion. TPF's 10 February 2026 visit still described the plant as under construction and expected commissioning later in 2026. JICA's May 2026 Senegal programme lists the wider Mamelles programme through 2029.
- Works package
- Initial 50,000 m3/day seawater reverse-osmosis plant expandable to 100,000 m3/day; seawater intake and pumping, intake transmission, brine discharge, treatment, product-water pumping and transmission, power connection, distribution-main installation and wider Dakar network renewal
- Marine interfaces
- Eiffage recorded a 340 m seawater-intake microtunnel drive in July 2025. The 2015 JICA preparation basis carried two 1,200 mm intake lines of about 350 m each and a 710 mm brine-discharge line of about 500 m, but later public construction updates reviewed by IMWO do not reconcile the final discharge geometry or publish marine acceptance.
- Commercial evidence boundary
- The main plant contract is in construction, not a new tender. The open specialist questions now sit at the interface between completed intake tunnelling, discharge installation, process commissioning and owner acceptance. The original 2025 completion date has passed, while the wider JICA programme continues beyond the plant's stated 2026 commissioning target.
Project timeline
Material developments
Dated events that changed scope, counterparties, delivery, commissioning or operating status.
Open this project in the Change LogThe plant remained under construction in its commissioning year
TPF's supervision visit confirmed active construction and an expectation of commissioning later in 2026, superseding the original 2025 completion plan without proving operating release.
SourceEiffage recorded the 340 m intake microtunnel milestone
The intake route moved from design into physical evidence. The update did not publish final brine-discharge installation or marine acceptance.
SourceThe main plant and operating order was announced
Toyota Tsusho identified the SONES client, consortium, initial 50,000 m3/day capacity and two-year O&M obligation, with an original 2025 completion plan.
SourceEvidence gap
What remains unverified
Outstanding evidence
- Final intake geometry and hydraulic testing
- Brine-discharge line, head and diffuser installation
- Marine survey and environmental acceptance
- Process wet commissioning and first water
- 50,000 m3/day performance test
- Power and product-water network readiness
- Owner operating release and two-year O&M start
- Phase 2 expansion boundary to 100,000 m3/day
Sources and related records
Read featured analysis Methodology Submit a correction Project tracker
Source collections
Project sources 6
- JICA cooperation programme for Senegal Japan International Cooperation Agency, Updated May 2026
- Mamelles desalination plant construction visit TPF, 10 February 2026
- Mamelles intake microtunnel and power-connection milestones Eiffage, 1 July 2025
- Toyota Tsusho receives Mamelles construction and operation order Toyota Tsusho, 1 June 2022
- Mamelles desalination project configuration and financing Société Nationale des Eaux du Sénégal, Current page reviewed 19 July 2026
- Mamelles seawater desalination preparatory survey Japan International Cooperation Agency, October 2015